I guess what I'm wondering now is if my quest for system mastery is already doomed to failure. Because I'm finding it hard to focus long enough to set those other, irreplaceable systems aside for even a short period of time. Because I love the quirks and idiosynracies of different systems, even the ones that could port over without losing their core essence. I read this brilliant post that integrates the Lawful-Chaotic alignment duality of Basic D&D and it makes me want to bust out some B/X dungeon crawl action. Ooh! There's a Lovecraftian horror-fantasy setting out for Pathfinder? Maybe it's time to dip my toe in the waters of that system; I like Paizo as a company, I like the solid thickness of the Pathfinder books and the loss-leader price on the Beginner Box... It's not just the setting or the genre, it's the idea of the system - yes, I could run a Classic D&D dungeon-crawl campaign with GURPS (Dungeon Fantasy) or Savage Worlds, and I could certainly adapt Shadows Over Vathak to any system of my choosing. But there's an undeniable pull to pairing setting/genre with the system it was written for.
At any rate, those distractions are culled just from examples of blog posts I read today. And I've made a point of un-following the blogs that tend to focus exclusively on flogging the latest available products in order to minimize the "ooh shiny" reflex, but even then I just can't get away from the siren call of other systems it seems.
Then again, maybe I'm just falling back into old patterns? Maybe the idea of committing to a single system just feels alien to me, so I go back to what's comfortable. Can I really pull of the monogameist lifestyle, or am I condemned to have a wandering eye the rest of my days?